Machine for bending u-bolts and the like



Filed Sept. 20, 1.956

W. F. RlKER MACHINE FOR BENDING U-BOLTS AND THE LIKE 4 Sheets-Sheet l INVENTOR. Wa/Ter E Biker ATTQRNEYS Dec. 22, 1959 w. F. RIKER MACHINE FOR BENDING u-BoLTs AND THE LIKE Filed Sept. 20, 1956 4 Sheets-Sheet 2 UMUDOWM HTTURNEYJ' Dec. 22, 1959 w. F. RIKER MACHINE FOR BENDING U-BOLTS AND THE LIKE 4 Sheets-Sheet 3 Filed Sept. 20, 1956 INVENTOR. Wa/fer E lfiker A TTORMEYJ Dec. 22, 1959 w. FIRIKER MACHINE FOR BENDING U-BOLTS AND THE LIKE 4 Sheets-Sheet 4 Filed Sept. 20, 1956 WM ME E r w w W Afro/281E 1.1

n Sggtfi MACHINE FOR BENDING U-BOLTS THE LIKE Walter F. Riker, Toledo, Ohio Application September 20, 1956, Serial No. 616,995

8 Claims. (Cl. 153-48) machine which will bend both wings of a U-bolt simultaneously around means for forming the semi-circular portion and which has adjustment mechanism to bend the wings to a greater or lesser degree depending upon the resiliency of the particular metal from which the bolt is formed.

It is another object of this invention to provide a U- bolt bending machine having a stationary forming pintle about which the semi-circular portion of the bolt is bent and which is readily replaceable with a pintle of different diameter to fabricate U-bolts of different diameters and thus with different spacings between their wings.

It is a still further object of this invention to provide a machine for bending both wings of a U-bolt simultaneously around a stationary forming pintle and having mechanism for preventing the resiliency of the stock from which the bolt is formed from springing the U-bolt out of shape either during or after its formation.

Other and more specific objects and advantages will be better understood from the specification which follows and from the drawings, in which Fig. 1 is a view in front quarter perspective of a machine embodying the invention;

Fig. 2 is a vertical, sectional view taken generally from the position indicated by the line 22 in Fig. 1, and being shown on a slightly enlarged scale;

Fig. 3 is a fragmentary, plan view on an enlarged scale of the bolt bending portions of the mechanism embodying the invention, with the parts shown in the position occupied at the beginning of a bending cycle;

Fig. 4 is a view similar to Fig. 3 but showing the parts in the position occupied at the end of a bending cycle;

Fig. 5 is a fragmentary, vertical, sectional view on an enlarged scale taken along the line 55 of Fig. 4;

Fig. 6 is a fragmentary, vertical section taken along the line 6-6 of Fig.2.

A machine embodying the invention has a crank 10 rotatably mounted by journals 11 on a movable table 12. The shaft of the crank 10 is driven by a belt and pulley generally indicated at 13 from a reducer l4 driven in turn by a motor 15.

The crank 10 is connected by a rod 16 to the rear end 'of a slide block 17. The block 17 is mounted by ways 18 on the upper flat face of a stationary table 19. A tenon 19a of the table 19 extends rearwardly between forwardly extending arms 21 of the table 12 and carries gibs 20 which slide in grooves 20a in the inner edges of the arms 21 (see Fig. 6).

2,918,101 Patented Dec. 22, 1959 The longitudinal spacing between the movable table 12 and stationary table 19 is adjustable by manually rotating a screw 22 which is threaded through downwardly extending portions of the movable table 12 and held in the tenon 19a of the movable table 19 by a thrust ball 23. Because the stroke of the crank 10 is determined by its size, the overall reciprocal stroke of the block 17 does not change, but by moving the movable table 12 closer to or farther away from the stationary table 19, i.e., by rotating the screw 22, the stroke of the block 17 relative to the stationary table 19 can be changed at will.

The block 17 has two cross head arms 24 extending laterally on opposite sides (see also Figs. 3 and 4), the outer ends of the crosshead 24 being bifurcated horizontally and vertically drilled to receive pivot pins 25 for the rear ends of a pair of horizontal, forwardly extending links 26. The links 26 are pivotally connected by pins 27 at their forward ends to the rear of a pair of forming slides 28. The slides 28 are mounted for recip rocation by horizontal ways 29 mounted on or formed in the inside vertical faces of a pair of way blocks 30.

As can best be seen by reference to Figs. 3 and 4, the way blocks 30 and the ways 29 carried thereby are angled inwardly toward each other so that the blocks 30 travel along intersecting paths lying in a horizontal plane.

Each of the slides 28 carries a horizontal forming roller 31 near its forward end, each of the rollers 31 being journalled upon a vertical pin 32.

Between the forward ends of the way blocks 30 the table 19 has a cutout 33 having a generally U-shaped contour and with a centrally located, rearwardly extending, peninsula 34. The rear end of the peninsula 34 is provided with mounting means for any one of several forming pintles, such as the large diameter pintle 35 shown in Fig. l and in solid lines in Figs. 3 and 4 or smaller diameter pintles, such as the smaller pintle 35a shown in Fig. 3 in broken lines. It will be observed in Fig. 3 that the pintle mounting means on the peninsula 34 is so designed that the surfaces of the pintles 35 or 35a are tangential to the same vertical, transverse plane when the pintles are mounted on the mounting peninsula.

Front faces 36 of the way blocks 36 lie in a vertical, transverse plane spaced rearwardly from the plane to which the pintle 35 is tangential a distance equal to the diameter of the bolts to be formed. Laterally adjustable stops 37 are mounted upon forward extensions 38 of the way blocks 30, being adjustable laterally so that the distance between the stop blocks 37 transversely of the machine is equal to the length of a U-bolt blank, i.e., a rod 39, before it is bent. The extensions 38 have flat tops lying in a horizontal plane at a level such that when a blank 39 is positioned between the stops 37, its ends rest upon the fiat tops of the extensions 38 in line with median grooves 4-0 of the rollers 31.

Rotation of the crank 10 in a counterclockwise direction (Fig. 2) drives the block 17 forwardly and through the links 26 moves the slides 28 forwardly on their ways 29. During the forward movement of the slides 28 the forming rollers 31 engage the blank 39 in their respective grooves 44 During continued forward movement of the slides 23 from the position shown in Fig. 3 to that shown in Fig. 4 the ends of the blank 39 are bent around the forming pintle 35. It will be observed by comparison between Figs. 3 and 4 that the length of the stroke of the slides 28 relative to the pintle 35 is such that the blank 39 is bent around the pintle 35 until its wings 39a and 3912 are bent inwardly beyond parallelism. This is necessary because of the resiliency of the material, usually steel, from which the blanks 39 are cut. If the wings 39a and 3% were bent only to parallelism, when the pressure of bending is removed, the wings 39a and 39b would spring apart slightly. By bending them beyond parallelism the slight resiliency remaining in the material spreads them only until they are parallel.

Because it is virtually impossible to know precisely h Ow far beyond parallelism the wings, 39a and 3912 must be bent so that they will spring apart to a parallel relationship, the machine embodying the invention is provided with the adjustment of'longitudinal position of the two tables 12 and 19 relative to each other and the slides 28 intheir ways 29 are inclined toward each other. If the material of which the blanks 39 are made is more resilient, themovable table 12 is cranked forwardiy closer to the stationary table 19, moving the forming pintle 35 closer to the crank 10 so that a stroke of the slides 23 passes farther beyond the forming pintle and bends the wings 39a and 39b closer together in initial formation. Conversely, if the material is less resilient, the table 12 is moved. away from the table 19 so that the wings 39a and 39b are not bent quite so far and upon release will separate only to parallelism. In order to adapt the machine for formation of U-bolts having semi-circular sections of smaller diameters, the pintle'35 is removed and a smaller diameter pintle substituted therefor. The two way blocks 30 are mounted by bolts 41 extending through transverse slots 42 in the table 19. By loosening the bolts 41 the two way blocks 30 can be slid inwardly a distance so that the slides 28 move the forming rollers 31 closely adjacent the sides of the forming pintle, in this case 35a.

A vertically movable backup bar 43 has a forwardly extending nose 44 and is mounted for vertical reciprocation in a block 45 positioned on the table 19 just back of the formingpintle 35. The bar 43 has a front, vertical face 46 lying in the same vertical, transverse plane as the front faces 36 of the way blocks 30. As can best be seen in Fig. 5, the upper end of the bar 43 is slotted with a vertical fore and aft slot 47 and a finger 48 is mounted therein by a transverse, horizontal pin 49. The bottom of the slot 47 is so shaped as to allow the finger 43 to be swung in a counterclockwise direction (Fig. during the upward movement of the bar 43 thus to allow the finger 48 to pass a blank 39 positioned between the front face 46 of the bar 43 and the forming pintle 35.

The lower end of the backup bar 43 (Fig. 2) is pivotally connected on the forward end of a walking lever 50 fulcrumed in an arm 51 extending downwardly from the bottom of the table 19. The rear end of the we king lever 50 is pivotally connected to a cam bar 52 extending upwardly through a central slot 53 in the table 19. The slot 53 serves as a slide for the bar 52. The upper end of the bar 52 is beveled and is aligned with and engaged by a beveled face 54 on the forward underside of ,the block 17.

When the block 17 is moved forwardly by a stroke of the crank its beveled face 54 strikes the upper end of the bar 52 rocking the walking lever 5b and raising the backup bar 43. The backup bar 43 moves upwardly behind one of the blanks 39 with its finger 49 being flipped in a counterclockwise direction to permitpassage. The mechanism is shown at this position in the cycle in Figs. 1, 3 and 5 while Fig. 2 shows the mechanism in the position where the block 17 first engages the upper end cause the central portion of the blank 39 to flex away from the center portion of the forming pintle 35 thus misforming both the circular section and the wings of the u bolt being bent. The small-amount of flexing of the blank 39 permitted by the slight clearance between the backup bar 43 and the forming pintle 35 is insufficient to significantly misform the finished U-bolt.

After the forward movement of the forming rollers .31 is completed (Fig. 4) and the crank 10 passes through its front deadcenter position, the return stroke of the mechanism takes place. The backup bar 43 remains up behind the central portion of the formed bolt until after the slides 28 have been returned a distance such that the forming rollers 41 are disengaged from the wings 39a and 39b of the U-bolt. Continued rearward movement of the mechanism including the block 17 allows a return spring 55 (Fig. 2) to swing the walking lever 50 and pull the backup bar 43 downwardly. The finger 48, being engaged above the central portion of the blank 39, forces the blank 39 downwardly off of the forming pintle 35 where it drops through the U-shaped opening 33 in the movable table 19.

Mechanism embodying the invention as illustrated the drawings is also shown as having a feeding maga zine and means for individually feeding U-bolt blanks from the magazine. The feeding magazine comprises a pair of spaced guideways 56 erected atop the way blocks 30 at their front sides 36. U-bolt blanks 39 are dropped into the guideways 56 and carried downwardly by gravity between the front faces 36 of the way blocks 39 and a pair of resilient clips 57 mounted at the lower end. of the guideways 56. The resilient clips 57 are so spaced from the front faces 36 of the way blocks 30 that each blank 39 falls to a level such that it can be separated from those blanks 39 above it by wedge shaped feeding fingers 58 mounted on top of the slides 28. As can best be seen in Fig. 2, each of the fingers 58 has an angular lower face 59 which separates one of the blanks 3? from those retained by the clips 57 and pushes it downwardly between the front faces 36 of the way blocks 30 and the forming pintle 35. Each of the fingers 53 has a flat top 60 located in a horizontal plane at a level such that it engages beneath the remaining ones of the blanks 39 in the guideways S6 and holds them up out of the way during the forming stroke.

Each reciprocation of the slides 28 thus picks off a blank 39, presses it downwardly between the faces 36 and pintle 35 with its lateral position controlled by the stops 37, holding the remaining blanks 39 up out of the way. As the slides 28 continue to move forwardly the forming rollers 31 engage the ends of the blank 39 and first form and then release the formed blank which is discharged by the finger'48 of the backup bar 43.

1 claim:

l. A machine for bending resilient bar stock into U- shaped items comprising, in combination, a stationary forming pintle having a surface contour corresponding to the contour of the central portion of the finished U-shaped item, a pair of coacting forming slides mounted for reciprocation along co-planar, linear, intersecting paths lying on opposite sides of and adjacent said forming pintle for bending the ends of said resilient bar stock around said pintle, drive means for reciprocating said slides aiong said paths, and means for mounting said pintle for longitudinal adjustment relative tosaid drive means whereby the arms of said resilient bar stock may be bent beyond parallelism as required in initial formation.

2. A machine for bending resilient U-bolts having parallel arms comprising, in combination, an upright stationary pintle mounted on a first section of said machine, a pair of forming slides mounted for reciprocatory movement along linear, intersecting pathslocated on opposite sides of said pintle, means for --po s itioning a. resilient U-bolt blank in working position closely adjacent the surface of said pintle-and extending transversely across said machine and the paths of movement of said slides, backup meaps for preventing the reverse movement of the center of said resilient blank significantly away from the surface of said pintle during bending, drive means for said slides mounted on a second section of said machine, and means for moving said sections longitudinally relative to each other whereby the arms of said resilient bar stock are bent selectively beyond parallelism on initial formation in compensation for the resiliency of said bar stock.

3. A machine according to claim 2 in which the backup means comprises a vertically movable bar and means for moving said bar into backup position after said blank is positioned against said pintle and said bar has an ejector thereon for pulling a finished bolt ofi the pintle by downward movement of said bar upon completion of a bending cycle.

4. A machine for bending U-bolts, said machine comprising, in combination, a sliding crosshead, crank means for reciprocating said crosshead along the longitudinal center line of said machine, a pair of forming slides, linear way blocks for mounting and guiding said slides, link means connecting said slides to said crosshead, said crank means being mounted on a first table, a second table, an upright stationary forming pintle having a surface contour corresponding to the contour of the central portion of the finished U-bolt and being centered on the center line of said machine and mounted on said second table, way blocks for said slides carried on said second table and positioned on opposite sides of such center lines with the linear paths of reciprocation of said slides extending past said pintle on opposite sides thereof, means for positioning a U-bolt blank closely adjacent said pintle normal to and centered on such center line, and means for adjusting the spacing of said tables along the center line of said machine and thereby moving said pintle longitudinally relative to the stroke of said forming slides.

5. A machine according to claim 4 in which the paths of reciprocation of said forming slides are correspondingly angled inwardly toward such center line and said forming slides bend the arms of the U-bolt blank inwardly beyond parallelism a distance determined by the position of the pintle relative to the stroke of the forming slides.

6. A machine according to claim 4 and a vertically zrecip'rocable backup bar movable upwardly after a blank is positioned in bending position closely adjacent said pintle for holding the center of said blank closely adjacent said pintle at the beginning of a bending cycle and said bar has an ejector thereon engageable with a formed U-bolt upon downward movement of said bar at the end of a bending cycle for ejecting said formed U-bolt from said machine.

7. A machine according to claim 6 and a feeding mechanism for U-bolt blanks, said mechanism comprising a vertical magazine located above the edge of the pintle around which a blank is bent by the forming slides and means on said slides for picking off a single blank from said magazine, for forcing such picked 01f blank into bending position and for holding the remain ing blanks up in said magazine.

8. A machine according to claim 7 in which said backup bar is moved upwardly by leverage actuated by engagement therewith of said crosshead and moved downwardly by return means.

References Cited in the file of this patent UNITED STATES PATENTS 459,859 Ellis Sept. 22, 1891 500,058 Strorn June 20, 1893 1,382,102 Lukaszewski June 21, 1921 1,812,046 Groehn June 30, 1931 1,860,828 Zalm May 31, 1932 2,427,949 Culkosky et al. Sept. 23, 1947 FOREIGN PATENTS 113,852 Great Britain Mar. 14, 1918 218,757 Great Britain July 14, 1924 

